Nice idea, but I think for THIS application the FOV is to large and the resolution (160*120?) is to low.
Of course the extraterrestrial knew that and therefore allowed the integration of the lapton chip into the phone <8-)
I use a dedicated thermal camera with bit higher resolution but higher FPS. As others have written they are quite useful as you see thing (even not ET) you could have measured with an IR thermometer if you knew they were there.